You don’t need to abstain from eating fruits three days before the glucose tolerance test, but you should pay attention to eating less food that is too sweet. Glucose tolerance, i.e. glucose tolerance test, is mainly used to understand the function of pancreatic β-cells and the body’s ability to regulate blood glucose, to see whether the body has impaired glucose regulation, and it is a method to diagnose diabetes mellitus, which is widely used in clinical practice. Within 3 days before doing the glucose tolerance test, the daily carbohydrate intake should be not less than 150g, which means that you should eat normally, at least three meals a day, one or two staple foods for each meal; you should fast after 12 o’clock in the evening of the day before the test, and you should fast for 8-10 hours before the test, so it is better to arrange the meal time in advance. During the examination, that is, in the two hours after drinking sugar water, do not smoke, do not drink alcohol, do not drink coffee and tea, do not do strenuous exercise. If you experience symptoms such as “three more and one less” (drinking more, urinating more, eating more, and losing weight), you should consult a doctor in time for diagnosis and treatment under the guidance of the doctor.